Microcontrollers are widely used to control many kinds of electronic devices. Microcontrollers may be also used in embedded systems within electronic devices and dedicated for particular tasks. A microcontroller may receive digital input signals, process the digital input signals, and generate digital output signals based on instructions stored in a memory. In some applications, a user may not need to interact with a microcontroller. For example, the microcontroller may be programmed with instructions and may operate without the need to change the instructions or without sending or receiving data from another device. However, in many applications, a microcontroller may need to communicate with a user or with a remote device.